Lexus ES300 (1997 year). Service manual - part 10

39

ENGINE — 1MZ-FE ENGINE

2) VCV (Vacuum Control Valve)

The VCV is a valve that regulates the intake
manifold vacuum that is applied to the VSV
to a constant level (-17 kPa, -130mm Hg).
The intake manifold vacuum that is supplied
through the S port is applied to the
diaphragm. If this force becomes greater than
the spring force, the diaphragm moves
downward, allowing the valve to close the S
port and the atmosphere supplied through the
filter. Conversely, if the vacuum that is
applied to the diaphragm becomes weaker,
the diaphragm moves upward, causing the
valve to open and to shut off the atmosphere
and supply the intake manifold vacuum. This
process is repeated to regulate the vacuum in
the Z port to a constant level.

3) EGR Valve Position Sensor

The EGR valve position sensor is mounted on the EGR valve. This sensor converts the EGR valve
opening into a voltage and sends it to the ECM as the EGR valve position signal.

40

ENGINE — 1MZ-FE ENGINE

Operation

The ECM executes duty control of the VSV to control the vacuum that has been regulated to a constant
level by the VCV, thus controlling the vacuum that is applied to the EGR valve.
Also, the EGR valve position sensor in the EGR valve detects the EGR valve opening to provide feedback
control to the ECM, thus achieving a target opening that is appropriate for the engine condition.

8. Others

A communication circuit has been provided between the ECM and the ABS & TRAC ECU in
conjunction with the adoption of the TRAC (Traction Control) system. The ECM sends signals such as
the throttle position signal and the engine speed signal to the ABS & TRAC ECU. In addition, the ECM
executes fuel cutoff in accordance with the request signals from the ABS & TRAC ECU.

41

CHASSIS — A451E AUTOMATIC TRANSAXLE

CHASSIS

A541E AUTOMATIC TRANSAXLE



 

DESCRIPTION

The A541E automatic transaxle used in the previous model is also used in the new model. However, the
pattern select switch has been discontinued.

 Specifications 

Transaxle Type

A541E

Item

A541E

1st

2.810

2nd

1.549

Gear Ratio

3rd

1.000

4th (Overdrive)

0.735

Reverse

2.296

Counter Gear Ratio

0.945

Differential Gear Reduction Ratio

3.933

Fluid Capacity

Transmission

6.8 (7.2, 5.9 )

p

y

liters (US qts, Imp. qt)

Differential

0.9 (0.9, 0.8)

Fluid Type

ATF D–II or DEXTRON



III (DEXTRON



II)

42

CHASSIS — DRIVE SHAFT

DRIVE SHAFT



 DESCRIPTION



The inboard joint of the drive shaft on the previous model was the bolt-mounted type. However, the new
model has adopted a friction-welded integrated joint.



The boot of the outboard joint are made of thermoplastic elastomer, which has superior durability.

 New 

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